The present invention relates to watches with calendar displays. More particularly, the present invention relates to watches having calendar displays and hands drives that are rotatably coupled to a setting shaft according to the axial position of the shaft.
A wrist watch with a setting shaft that may be locked in two different axial positions is known from German DE-AS No. 2,253,505. In the first or preselection axial position, a rocker ratcheting through an intermediate correcting wheel of the setting shaft is deflected against an elastic restoring force during manual rotation of the setting shaft in one direction. The rocker acts as an actuating lever, when the setting shaft is pulled into the second axial position, for a coupling element that may be switched between two working positions. Following preselection, i.e., the rotation of the setting shaft in one direction in the first axial position to deflect the rocker from the rest position, a rotating clutch drive connection is established between the setting shaft and a hand setting gear to engage the hour gear. In other words, after the moving of the setting shaft into the pulled-out or second position, the hands may be rotated in the one or the other direction manually, by a rotating motion of the setting shaft. If preselection has occurred by rotating the setting shaft in the opposite direction in the depressed or first axial position, the rocker is deflected in the reverse direction and upon the pulling of the setting shaft to the second position a rotating clutch connection is established by the coupling element between the setting shaft and the monthly date display disk (without engaging the hand drive gear). The rotation of the pulled-out setting shaft effects the forward movement of the date display disk, together with the day-of-the-week display disk. The-day-of-the-week display disk is actuated by a free-wheeling ratchet bevel gear drive which is disengaged from the day-of-the-week display disk during a rotation of the date display disk in the opposite direction.
A disadvantage of this known watch equipped with a setting device is the complicated structure and the mode of operation of the rocker as the preselector and the actuating device for the switching of the coupling element. This complex structure may be susceptible to wear. Also, from the standpoint of handling, the lack of an apparatus for the independent setting of the day-of-the-week display disk may be inconvenient. Furthermore, the use of a common coupling element to establish clutch drive connections to both the calendar display and the time indicators has proved to be highly space consuming, which is contrary to the trend of constantly decreasing the dimensions of the works of wrist watches.
German DE-AS No. 2,004,224 discloses a wrist watch equipped with a spring drive and having a setting device for the date display and the hands which setting device facilitates rapid corrections. In this watch, in a slightly extracted axial position of the setting shaft an intermediate gear is inserted through two cooperating levers in a setting gear of the setting shaft. In the semi-extracted position of the setting shaft, this intermediate gear sits with a journal like frustum on the cylindrical surface of the setting shaft. The intermediate gear engages a coupling element with a star shaped control element rotatably mounted in an arcuate slit. Depending on the direction of rotation of the setting shaft and thus of the intermediate gear, the coupling element is moved to one of the two ends of the arcuate slit, where, during further rotation of the setting shaft the coupling element engages the star gearing of the date display disk in order to adjust the display disk in a stepped manner. In the alternate case, i.e., with rotation of the setting shaft in the opposite direction, the coupling element engages in a similar manner with the day-of-the-week display disk. In the fully extracted position of the setting shaft, the journal-like frustum of the intermediate gear slides down on a conically pointed end of the setting shaft. The intermediate gear is then disengaged from the gear of the coupling element and engages an interchangeable gear for the setting of the hands, in the clockwise or counterclockwise direction depending on the direction of the rotation of the setting shaft.
A disadvantage of this type of arrangement for a rapid date setting device is again the increased space requirement caused by the height adjustable intermediate gear for selective coupling with the hand setting gear or the rotating coupling element, depending on the extracted position of the setting shaft. Furthermore, there is the disadvantage that in the calendar display adjusting position no stationary, stable working position is provided for the coupling element. The necessary gear engagement is obtained by the constant application of torque to the setting shaft. With respect to the handling technique, there is also the particular disadvantage that the display disks for the calendar indication are adjustable in one direction only, i.e. not in both the forward and backward directions.
In the German patent application P No. 2,855,898, the present applicant has proposed a watch of this general type, wherein either the date display or the day-of-the-week disks may be adjusted independently by use of a switching lever ratcheting on an intermediate gear. The position of the switching lever is determined by the direction of the rotation of the shaft in a preselection axial position of the setting shaft. By extracting the setting shaft into the next axial position a corresponding shift is effected by a preselecting lever through the displacement of a switching element to rotate a coupling element in a slit curved in the shape of an S. In order to set the hands, the setting shaft must be brought into a further extracted position, i.e., into a third axial position. A setting gear is provided on the front end of the setting shaft and is located inside the works to engage a crown wheel fixedly attached to the works at the third position in order to effect a rotation of the hands. The calendar setting gear is disengaged in this particular position.
This proposed rapid setting device for a watch of this general type has the advantage that the calendar adjustment may be predetermined by preselection in a position of the setting shaft and that the adjustment may then be effected, following the moving of the shaft into the next axial position, by rotating the shaft in either direction, i.e., forward and backward. A disadvantage of this watch, however, again lies in the use of a lever, changed over by the actuation of the shaft during preselection, for the displacement of the coupling element in the one or the other direction and also the parts susceptibility to wear because of the ratchet action of the lever on the intermediate gear. Another disadvantage is the relatively great space requirements due to the fact that the setting of the calendar display requires a setting gear on the setting shaft and also this watch requires an independent setting gear in front of the setting shaft with a hand setting crown wheel.
Accordingly, it is an object of the present invention to provide a watch of the above-described general type with rapid setting capability of a hand and calendar adjusting device. A further object is to reduce space requirements and provide a mode of operation that is functionally reliable and easy to operate.
These objects and others are achieved by the present invention in a watch having a highly compact structural layout and thus low space requirements within the works, while providing a relatively simple design that enhances the ease of operation and is not susceptible to wear. These advantages result from the fact that in contrast to known watches, the present invention employs an intermediate gear fixedly mounted within the works and thus immobile both in the axial and transverse directions during the axial displacements of a setting shaft. The intermediate gear is arranged centrally and provided with a central function. The intermediate gear engages both a setting gear for the hands and a coupling element for the selective adjustment in any direction of the calendar display disks. The setting gear is located within the path of the setting shaft and is capable of being lifted off of the setting shaft. The coupling element is provided with three point switching capability including two stable working positions and is subject to manual preselection by the setting shaft. Further, the coupling element operates with particular reliability, because wear associated with a ratchet coupling and with support functions of preselection reversing levers (as in the case for the example of the above-described rocker with a complicated geometrical layout of the cooperating parts) no longer appears. Furthermore, the number of parts to be moved and caused to engage each other is reduced and the geometry of the arrangement is simplified.
In the first or depressed axial position of the setting shaft of the present invention, a preselection of the adjustment of the calendar display is effected dependent upon the direction of rotation of the setting shaft. Rotation of the setting shaft moves the coupling element into one of two intermediate preparatory positions while further rotation of the setting shaft results in a free rotation of the coupling element in the preparatory position, but not in any wear inducing engagement. When subsequently the setting shaft is extracted by one notch into a second axial position, a triangular slotted link acts upon the coupling element and depending upon which of the two preparatory positions has been reached in the intermediate position of the rotating coupling element, the element will be rotated by one of the two switching areas of the slotted link into a working position. The rotation of the coupling element effects a setting engagement with the date or day-of-the-week display disk, such that the display disk involved may be rotated by steps forward or backward, depending upon the rotation of the setting shaft in the second axial position.
In a second extracted position, i.e., a third axial position of the setting shaft, the slotted link is returned and the coupling element thereby brought into an intermediate position from its previous working position, and thus disengaging the calendar display disks. At the same time, the setting drive gear of the hands is displaced along its axis and is rigidly coupled in rotation with the setting shaft in order to render the selective forward or backward setting of the hands possible.
Within the scope of the invention, the correlation of the axial positions of the setting shaft with the individual adjustments or preselection functions may be selected in a manner different from that summarily described hereinabove. The correlation described is however preferred with quartz controlled electronic timing circuits since the need for an adjustment of calendar displays arises substantially more often, i.e., approximately once a month, than the requirement of setting the hands. Furthermore, it is an advantage from an operational standpoint that in the rest position, i.e., in the depressed or first axial position of the setting shaft, a playful or erroneous rotation of the setting shaft has no effect on the display function or on the normal drive function of the works. As mentioned hereinabove, rotation of the shaft in the first axial position merely rotates the coupling element into one of the two preparatory positions being the terminal settings of the intermediate position between the two working positions. Thereafter, the coupling element rotates freely without any engagement.
According to the preferred embodiment of the present invention, the slotted link for aligning the coupling element in the preselected working position is a self-securing arrangement. Consequently during the calendar display adjustment in the second axial position of the setting shaft, there is no need for any force to be applied by the setting shaft to maintain the working position of the coupling element.
According to a further feature of the present invention, a correction spider for engaging the calendar display is rotatably coupled to the coupling element by friction. Also, a correction wheel of the calendar display engages the teeth of the intermediate gear. This arrangement prevents interference with the switching of the calendar display which could occur while the coupling element was in the working position by a rigid gear connection to the manually actuated setting shaft. The frictional engagement permits the drive gear of the hands to execute the stepping motion of the calendar display even with a manually arrested setting shaft by rotating the correction spider with respect to the correction wheel of the calendar display of the coupling element.
It is further preferred that the gear connection between the setting shaft and the coupling element according to the present invention be provided with a certain backlash of the rotating motion between the setting shaft and the coupling element. The backlash may be attained by providing a clearance between at least two cooperating torque transmitting elements. This prevents the cancellation of a preselection of the coupling element effected in the first position by an accidental slight backward movement of the setting shaft during extraction into the second or actuating axial position. In this way, the action of the slotted link against the coupling element results in the working position corresponding to the preselection for the rapid adjustment of the calendar display.